I haven’t yet taken one of Industrial Metal Supplies’ patina classes,
but only because I’m consistently out of town when they hold them
here. I’ve been aregular customer of sheet copper, patina, and
de-greaser for years. I’ve had some great conversations with their
patina experts. Their M-24 patina is the best thing I’ve found for a
black background on copper. It also works onbrass and nickel.
Epaul - Gem Artist